The amount of energy which is used daily throughout the world
is a huge number. A brief answer to this question would show that
our lives are built around energy. For example, humans need the
chemical energy supplied by food in order to survive. A person
would find it difficult to live without heat energy to warm their
house or cook their food. Tremendous amounts of energy run machines
to make consumer products. A great deal of energy is used for
transportation. The average person uses about eight times as much
energy as could be produced by muscle power alone. It is a known
fact that the average person in the United States expends more
than ten times the energy of an average person in most other parts
of the world.

The long upward trend in global commercial energy production
and consumption continued through 1993, the most recent year for
which data are available. Global energy production in 1993 reached
338 exajoules (1 exajoule = 1018 joules,
or ~163 million barrels of oil), which is 40% greater than that
in 1973. Total energy consumption rose to 326 exajoules,
which is 49% greater than that in 1973. The energy consumption
of Europe in 1993 was 93 exajoules, which indicates that
Europe accounted for almost 30% of the global energy consumption.

Energy use creates serious problems. They include the depletion
of fuel reserves and environmental effects. Energy depletion has
occurred partially due to the increased standard of living, however,
a major decrease is markedly noticed in the industrial development
of manufactured goods. Alternative sources of energy must be considered,
since fossil fuel reserves will be used up fairly soon.

It is necessary to develop new ways of obtaining energy and
one such method is nuclear fission, in which nuclear plants work
to split atoms in certain radioactive elements. The process of
nuclear fission releases energy, and kinetic energy of nuclear
fission fragments produces heat, which can be used in making steam
for generating electricity. Another possible method to obtain
energy is through solar energy, in which the sun's energy can
be collected and concentrated by flat plate panels on the roofs
of buildings and used to heat a circulating fluid. Other methods
which can be used to obtain energy are biomass conversion, tidal
power, geothermal energy, and nuclear fusion. In order for industrialized
regions to maintain high living standards, they must develop cleaner,
more renewable energy sources.